A known base plate cooling structure is based on a simple and inexpensive technology employed in car radiators, in which a cooling fluid, such as a cooling liquid, is fed at one end of a base plate into one inlet pipe, wherefrom the fluid is distributed into flow channels of the base plate and is discharged through one outlet pipe at the opposite end of the base plate into the cooling system.
However, a long flow channel can lead to an imbalance in temperature. This imbalance can arise when the cooling liquid becomes warm as it propagates in the flow channel, whereby a base plate of symmetrical dimensions is unable to transfer heat evenly to the warmer and warmer cooling liquid. Accordingly, as the cooling liquid gets gradually warmer, an exothermal electric component at the last position in the cooling circulation, such as a loss source, e.g. a semiconductor module or a resistor, may run the hottest.